Fixed issue where RegExp greedy jit code loops when no input is
consumed. Changed the code to only loop if some input was consumed,
but fall through if we successfully match an alternative that
doesn't consume any input.
https://bugs.webkit.org/show_bug.cgi?id=42664

Added tests to correspond to the changes made in
JavaScriptCore/yarr/RegexJIT.cpp to fix
https://bugs.webkit.org/show_bug.cgi?id=42664.
Note that some of the new test cases fail due to one or more
unrelated bugs in the pcre interpreter. The expected results
for these tests will need to be updated when the implementation
conforms to the JS standard.